Operation; Checking Instruments; Fault Indication; Engine Speed Control - Volvo TD420VE Operator's Manual

Operation

Correct operation technique is very important for both fuel economy and engine life. Always let the engine warm
up to normal operating temperature before operating at full power. Avoid sudden throttle openings and operation
at high engine speeds.

Checking instruments

Check all instruments directly after starting, and then
regularly during operation.
IMPORTANT! The lubrication oil level must be
checked every 8 hours on engines which oper-
ate continuously. Please refer to the "Mainte-
nance, lubrication system" chapter:

Fault indication

If the EDC4 system receives abnormal signals from
the engine, the "Diagnostic lamp" will start to flash. By
pressing the "Diagnostic button", a fault code can be
received which can guide fault tracing (or a fault code
can be received via the CAN network).
More information about fault codes and fault tracing
is found in the "Diagnostic function" chapter.
Effect on engine
The diagnostic function affects the engine in the fol-
lowing ways:
1. The diagnostic function has discovered a minor
malfunction which does not damage the engine.
Reaction: The engine is not affected. The diag-
nostic lamp lights up.
2. The diagnostic function has discovered a serious
malfunction which will not immediately damage
the engine (e.g. high coolant temperature):
Reaction: The engine goes into "limp home"
mode. The diagnostic lamp lights up.
3. The diagnostic function has discovered a serious
malfunction which makes it impossible to control
the engine.
Reaction: The diagnostic lamp starts to flash.
Engine is shut off.
16

Engine speed control

Avoid sudden and violent throttle opening.

Operation at low load

Avoid long-term operation at idle or at low load, since
this can lead to increased oil consumption and even-
tually to oil leakage from the exhaust manifold, since
oil will seep past the turbocharger seals and accom-
pany the induction air into the inlet manifold at low
turbo boost pressure.
One consequence of this is that carbon builds up on
valves, piston crowns, exhaust ports and the exhaust
turbine.
At low load, the combustion temperature is so low
that full combustion of the fuel can not be ensured,
which means that the lubrication oil can be diluted by
diesel fuel, and the exhaust manifold will eventually
leak oil.
If the following points are done as a complement
to normal maintenance, there will be no risk of
malfunctions caused by operation at low load.
•
Reduce operation at low load to a minimum. If
the engine is regularly test run without load once
a week, operation duration should be limited to 5
minutes.
•
Run the engine at full load for about 4 hours once
a year. This gives carbon deposits in the engine
and the exhaust pipe a chance to be burned
away.